What is a Hammock?

A Fijian family lives below me. They have two young sons, and there is another boy the age of their sons that lives next door. When I am outside doing laundry or reading in my hammock they'll come bug me, its kind of silly because they speak little English and I speak little Fijian. Prior to seeing my hammock, they had never seen one or been introduced to the concept. I showed them how to set it up and let them play on it, they loved it. Next time I'm going to bring out my (American) football and play some pigskin with them. Though they'll most likely just play rugby with it...